Computing devices such as personal computers, smartphones, and tablets may serve as user portals to access a variety of multi-user systems, such as online technical-support systems, multi-user gaming systems, and other multi-user systems. Such computing devices may communicate with servers of the multi-user systems to convey information between users of the system. Multi-user systems are generally configured to provide access to stored information based on users' memberships in system-defined user groups. This may inconvenience users, who may be unable to access desired information or may be required to transfer or search through large volumes of available information to find desired information. Additionally, users may be required to provide the same information multiple times when interacting with the system.